A while back there was a discussion here about making a nice round hole
bigger. One solution that was suggested was to get a special hole saw that
allowed you to use a smaller longer bodied hole saw in the middle as a pilot
and the larger new correct size hole saw on the out side.

I had to change to a sink faucet yesterday, and the fancy one my wife picked
out would not reach all the way through the multiple layers of the counter
top. With tile on top, a layer of unknown material, the sink itself, and
then a layer of plywood below it was just too much material. I dug through
the box of hole saws in my truck and noticed that different diameters and
brands were of different lengths. When I looked at my arbors I noticed one
had longer threads than the rest.

I selected a hole saw that was the same diameter as the existing hole, and
one that was a little larger than the outside diameter of the nut that would
tighten the faucet in place. I screwed on the larger hole saw, and then the
smaller one. It looked perfect, and ultimately it was. I cut a hole
through the bottom layer of plywood up to the bottom of the sink itself.

It worked like a charm. Everything is in place and all nice and solid and
sealed. Being in the trades I probably would have eventually figured out a
way to do this, but thanks to everybody here I was able to instantly
formulate a solution.

You guys made me look like a hero. Thanks guys.

Bob La Londe
www.YumaBassMan.com